Problem: Daniel did 38 fewer push-ups than Umaima in the evening. Umaima did 45 push-ups. How many push-ups did Daniel do?
Umaima did 45 push-ups, and Daniel did 38 fewer than that, so find the difference. The difference is $45 - 38$ push-ups. She did $45 - 38 = 7$ push-ups.